Lexus ES300 (2002 year). Service manual — part 370

VSV is ON

VSV is OFF

Air

F

E

Air

F

E

A52140

VSV is ON

VSV is OFF

E

F

E

F

Air

Air

A12540

VSV is ON

VSV is OFF

Air

E

F

Air

E

F

A52143

-

DIAGNOSTICS

SFI SYSTEM (1MZ-FE)

05-99

252

WIRING DIAGRAM

Refer to DTC P0440 on page

05-88

.

INSPECTION PROCEDURE

HINT:

If DTC P0441, P0446, P0450 or P0451 is output after DTC P0440 or P0442,first troubleshoot DTC
P0441, P0446, P0450 or P0451. If no malfunction is detected, troubleshoot DTC P0440 or P0442 next.

Read freeze frame data using hand-held tester or OBD II scan tool. Because freeze frame records
the engine conditions when the malfunction is detected. When troubleshooting, it is useful for deter-
mining whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio
was lean or rich, etc. at the time of the malfunction.

When the ENGINE RUN TIME in the freeze frame data is less than 200 seconds, carefully check the
vapor pressure sensor.

Hand-held Tester:

1

PERFORM ACTIVE TEST BY HAND-HELD TESTER

(a)

Select the ACTIVE TEST mode on the hand-held tester.

(b)

Disconnect the vacuum hose from the VSV for the EVAP.

(c)

Start the engine.

(d)

Select the item ”EVAP VSV(ALONE)” in the ACTIVE
TEST and operate the VSV for EVAP.

(e)

When the VSV for the EVAP is operated by the hand-held
tester, apply the disconnected hose to your finger to
check the suction.
Result:
VSV is ON: Disconnected hose sucks.
VSV is OFF: Disconnected hose does not suck.

(f)

Select the item ”CAN CTRL VSV” in the ACTIVE TEST
and operate the VSV for CCV.

(g)

Check the VSV for CCVoperation when it is operated by
the hand-held tester.
Result:
VSV is ON: Disconnected hose sucks.
VSV is OFF: Disconnected hose does not suck.

(h)

Select the item ”TANK BYPASS VSV” in the ACTIVE
TEST and operate the VSV for pressure switching valve.

(i)

Check the VSV for pressure switching valve operation
when it is operated by the hand-held tester.
Result:
VSV is ON: Disconnected hose sucks.
VSV is OFF: Disconnected hose does not suck.

05-100

-

DIAGNOSTICS

SFI SYSTEM (1MZ-FE)

253

NG

REPAIR OR REPLACE

OK

2

PERFORM ACTIVE TEST BY FOR EVAPORATIVE EMISSIONS LEAK

(a)

Connect the hand-held tester to the DLC3.

(b)

Select the ”EVAP SYS CHECK” mode on the hand-held tester.

(c)

Perform ”EVAP SYS CHECK”.
DISPLAY:

A

B

C

Scan tool detects a leak

on the fuel tank side.

Scan tool detects a leak

on the canister side.

Scan tool does not detect a leak

in the EVAP system.

B

Go to step 7

C

CHECK VACUUM HOSES

A

3

CHECK FUEL TANK CAP ASSY(TOYOTA GENUINE PARTS)

(a)

Replace to Toyota genuine parts.

(b)

After replace, perform ”EVAP SYS CHECK” by hand-held tester. (Go to step 2.)

OK

Go to step 4

NG

REPLACE TO TOYOTA GENUINE PARTS

4

CHECK THAT FUEL TANK CAP IS CORRECTLY INSTALLED

(a)

Correctly install fuel tank cap.

(b)

After install, perform ”EVAP SYS CHECK” by hand-held tester. (Go to step 2.)

OK

Go to step 5

NG

CORRECTLY INSTALL FUEL TANK CAP

5

INSPECT FUEL TANK CAP ASSY (See page

12-6

)

(a)

Replace to fuel tank cap assy.

(b)

After replace, perform ”EVAP SYS CHECK” by hand-held tester. (Go to step 2.)

OK

Go to step 6

NG

REPLACE FUEL TANK CAP ASSY

-

DIAGNOSTICS

SFI SYSTEM (1MZ-FE)

05-101

254

6

CHECK FUEL TANK INLET PIPE SUB-ASSY (FOR DAMAGE)

(a)

Remove the fuel tank cap.

(b)

Visually inspect the fuel inlet pipe for damage.

(1)

Replace to fuel tank inlet pipe sub-assy.

(2)

After replace, perform ”EVAP SYS CHECK” by
hand-held tester. (Go to step 2)

(c)

Repair or replace to fuel tank cap assy.

(d)

After repair or replace, perform ”EVAP SYS CHECK” by hand-held tester. (Go to step 2)

NG

REPLACE FUEL TANK INLET PIPE SUB-ASSY

OK

REPLACE VACUUM HOSES (VAPOR PRESSURE SENSOR - FUEL TANK, FUEL TANK - VSV FOR
PRESSURE SWITCHING VALVE)

7

CHECK FUEL HOSE (VSV FOR PRESSURE SWITCHING VALVE - CHARCOAL
CANISTER)

NG

REPAIR OR REPLACE

OK

8

CHECK EACH VSV CONNECTOR FOR LOOSENESS AND DISCONNECTION

NG

REPAIR OR CONNECT VSV AND SENSOR
CONNECTOR

OK

9

CHECK VACUUM HOSES(8,9,10 AND 11 IN CIRCUIT DESCRIPTION)

(a)

Check that the vacuum hose is connected correctly.

(b)

Check the vacuum hose for looseness and disconnection.

(c)

Check the vacuum hose for cracks, hole, damage and blockage.

NG

REPAIR OR REPLACE

OK

A53763

VC

E2

A53769

PTNK

E2

05-102

-

DIAGNOSTICS

SFI SYSTEM (1MZ-FE)

255

10

INSPECT ECM(CHECK VOLTAGE)

(a)

Turn the ignition switch ON.

(b)

Measure voltage between terminals VC and E2 of the
ECM connector.
Voltage: 4.5 - 5.5 V

NG

CHECK AND REPLACE ECM

OK

11

INSPECT ECM(CHECK VOLTAGE)

(a)

Remove the fuel tank cap.

(b)

Turn the ignition switch ON.

(c)

Measure the voltage between terminals PTNK and E2 of
the ECM connector.
Voltage: 3.0 - 3.6 V

OK

Go to step 13

NG

12

CHECK HARNESS AND CONNECTOR(VAPOR PRESSURE SENSOR - ECM)

NG

REPAIR OR REPLACE HARNESS AND
CONNECTOR

OK

REPLACE VAPOR PRESSURE SENSOR ASSY